|number|symbol|name|21st|22nd|23rd|24th|25th|26th|27th|28th|29th|30th|
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|21|Sc|scandium|582163||||||||||
|22|Ti|titanium|602930|639294|||||||||
|23|V|vanadium|151440|661050|699144||||||||
|24|Cr|chromium|157700|166090|721870|761733|||||||
|25|Mn|manganese|158600|172500|181380|785450|827067||||||
|26|Fe|iron|163000|173600|188100|195200|851800|895161|||||
|27|Co|cobalt|167400|178100|189300|204500|214100|920870|966023||||
|28|Ni|nickel|169400|182700|194000|205600|221400|231490|992718|1039668|||
|29|Cu|copper|174100|184900|198800|210500|222700|239100|249660|1067358|1116105||
|30|Zn|zinc|179100||||||||||
|36|Kr|krypton|85300|90400|96300|101400|111100|116290|282500|296200|311400|326200|
|42|Mo|molybdenum|87000|93400|98420|104400|121900|127700|133800|139800|148100|154500|

Question: how many names are listed on the chart?
Answer: 12